Severe economic loss has heretofore been caused by frost damage of crops, such as fruit and vegetables. Previous attempts to prevent frost damage of crops have been limited to the use of smudge pots, bonfires, water spraying and air movement by fans or airplanes. While remotely collected solar energy has heretofore been used for heating water and for heating a transfer fluid to be supplied to an indoor space, I am not aware of any attempts to apply solar energy heating concepts to the maintenance of vegetation above frost damage levels. Furthermore, while tubularly encased phase change material has heretofore been suggested for thermal energy storage purposes, such as in my prior patents: U.S. Pat. No. 4,223,666 for Toroidal Solar Collection and Energy Storage Apparatus; U.S. Pat. No. 4,248,209 for Coupled Toroidal Solar Collector, granted Feb. 3, 1981; and U.S. Pat. No. 4,250,958 for Double Tubular Thermal Energy Storage Element granted Feb. 17, 1981, no suggestion has heretofore been made concerning use of such material to surround vegetation.
Similarly, my aforementioned prior patents directed to Toroidal Solar Collection and Energy Storage, while teaching the use of stacks of automotive tires as a collector of solar energy, do not deal with the purposes of the present invention.